Jadis JA-200 Mk. II Amplifiers

[Diapason]

My understanding of Jadis has always been that they've made incremental changes along the way. I strongly suspect that the mk II moniker is to get us talking rather than a huge leap from whatever the last of the mk I versions was. But that's just a baseless opinion.

 

[KeithR]

Davey, I certainly apologise if I was hasty, but it is puzzling that literally two days ago Jadis told me to expect a review of the JA200 in Stereophile. So this could be merely a coincidence and a truly new review of the JA200 Mk. II could be forthcoming soon?

Jason Serinus said he was trying to get a pair in for review from one of the show reports a year ago

 

[DaveyF]

My understanding of Jadis has always been that they've made incremental changes along the way. I strongly suspect that the mk II moniker is to get us talking rather than a huge leap from whatever the last of the mk I versions was. But that's just a baseless opinion.

Actually, I think a lot of this conjecture ( regarding the new Jadis line) is actually wrong...and nothing but conjecture. I heard the older model 80 on a couple of occasions. Nice amp, but IMO not as resolving as other competitors at the time...
However, while I have not heard the new 80 mk2, the 30mk2 is far more resolving than any Jadis amp in my experience ( and most other tube amps I have heard, and I have heard a lot of them over the many years...including several current contenders). Also, i would severely doubt that the older models can be 'upgraded' to the current Mk2 status. Main reason being that the new KT150 tube has to work with the transformers...and the older models do not have transformers that can support this tube.
I can say with certainty, that if I owned an older JA 30--or even a JA 200, it would be for sale now and I would have the new mk2's in my sights. Luckily, I wasn't in that position, LOL.

 

[JackD201]

Actually, I think a lot of this conjecture is actually wrong...and nothing but conjecture. I heard the older model 80 on a couple of occasions. Nice amp, but IMO not as resolving as other competitors at the time...
However, while I have not heard the new 80 mk2, the 30mk2 is far more resolving than any Jadis amp in my experience ( and most other tube amps I have heard, and I have heard a lot of them over the many years...including several current contenders). Also, i would severely doubt that the older models can be 'upgraded' to the current Mk2 status. Main reason being that the new KT150 tube has to work with the transformers...and the older models do not have transformers that can support this tube.
I can say with certainty, that if I owned an older JA 30--or even a JA 200, it would be for sale now and I would have the new mk2's in my sights. Luckily, I wasn't in that position, LOL.

The JA 200 Mk1 never impressed me. Their limits were always too easily reached and when passed.....one expected failures to quickly follow. After all when one goes for a high power tube amp, it is usually expected that the owner plans to be driving a tough load and/or to be doing some tough driving. The JA 30 Mk1 however will always have a special place for me and IMO is destined for vintage classic status. Not only did it sound great, it was probably the most dependable of them all. The KT 150 is a seriously good tube to build around marrying the openness of the KT88 and the oomph of the 6550. I would very much like to hear what Jadis has done with this tube. Mind you the time span of the launch of the Mk1 and the Mk2 is over a decade. We all know a lot can happen in that many years especially in the hands of talented designers and engineers. I expect a big leap perhaps not so much in house sound as that is aesthetic, perhaps positive evolutions there, but more so in reliability.

 

[bonzo75]

Ron I forgot to mention my jadis were on shun Mook and Nat weren't (too heavy) so possibly that's why jadis sounded more musical. This gets filed under Ron doesn't believe it (yet) but true

 

[DaveyF]

The JA 200 Mk1 never impressed me. Their limits were always too easily reached and when passed.....one expected failures to quickly follow. After all when one goes for a high power tube amp, it is usually expected that the owner plans to be driving a tough load and/or to be doing some tough driving. The JA 30 Mk1 however will always have a special place for me and IMO is destined for vintage classic status. Not only did it sound great, it was probably the most dependable of them all. The KT 150 is a seriously good tube to build around marrying the openness of the KT88 and the oomph of the 6550. I would very much like to hear what Jadis has done with this tube. Mind you the time span of the launch of the Mk1 and the Mk2 is over a decade. We all know a lot can happen in that many years especially in the hands of talented designers and engineers. I expect a big leap perhaps not so much in house sound as that is aesthetic, perhaps positive evolutions there, but more so in reliability.

Jack, that is exactly right. This is one of the reasons that I did not go for the new JA 200Mk2, because even if it would work in my small room ( with the heat build up...which for me is a major factor; perhaps less so for others), the other points that you brought up are a concern. The JA 30 and the new JA30mk2 have been the only amps in the Jadis line that I was, and am, interested in. As one steps up in power, at least in the Jadis line, you step up in complexity, heat build up, cost and a host of other points...which would lead me to hesitate! Plus, i happen to believe that the JA 30Mk2 is the best sounding and reliable of their offerings. ( assuming of course that one can match it to their speakers, a VERY big proviso). I knew to a very high certainty that my speakers would be a great match up with this amp...and at this point, I am right.

 

[microstrip]

Actually, I think a lot of this conjecture ( regarding the new Jadis line) is actually wrong...and nothing but conjecture. I heard the older model 80 on a couple of occasions. Nice amp, but IMO not as resolving as other competitors at the time...(...)
I can say with certainty, that if I owned an older JA 30--or even a JA 200, it would be for sale now and I would have the new mk2's in my sights. Luckily, I wasn't in that position, LOL.

Yes, we only have a lot of conjecture, no facts at all from any one ... But you could put an end to it easily just taking the bottom cover of you JA30 mkII and posting a few good pictures of it!

 

[Ron Resnick]

Ron I forgot to mention my jadis were on shun Mook and Nat weren't (too heavy) so possibly that's why jadis sounded more musical. This gets filed under Ron doesn't believe it (yet) but true

Okay!

 

[DaveyF]

Yes, we only have a lot of conjecture, no facts at all from any one ... But you could put an end to it easily just taking the bottom cover of you JA30 mkII and posting a few good pictures of it!

Micro, once again conjecture ( the highlighted part of your post). Even if that was easy, why would i have any inclination to do that???

 

[DaveyF]

Davey, I apologize. I saw the link on the way to dinner, and I had in my head that literally two days ago Jadis told me to expect a review of the JA200 in Stereophile.

A good example of expectation bias on my part, I think.

Ron,as they say down under...no worries mate.

 

[microstrip]

Micro, once again conjecture ( the highlighted part of your post). Even if that was easy, why would i have any inclination to do that???

Well, I have taken the bottom plate of several Jadis and it was a two minute affair ...

See the photo of the cj LP275m I was cleaning this afternoon. Sometime ago, some people questioned some aspects of its design, as soon as I posted the photo all was clear as pure water ... All the signal capacitors were of the CJD top telfon type!

 

[BruceD]

Ha!--if your Jadis keeps popping those "pesky" 150 Ohm resistors across the tubes-as I found with my earlier models--

then you might as well keep the Plate off anyway!

Sorry chaps

BruceD

 

[Zero000]

Jack, that is exactly right. This is one of the reasons that I did not go for the new JA 200Mk2, because even if it would work in my small room ( with the heat build up...which for me is a major factor; perhaps less so for others), the other points that you brought up are a concern. The JA 30 and the new JA30mk2 have been the only amps in the Jadis line that I was, and am, interested in. As one steps up in power, at least in the Jadis line, you step up in complexity, heat build up, cost and a host of other points...which would lead me to hesitate! Plus, i happen to believe that the JA 30Mk2 is the best sounding and reliable of their offerings. ( assuming of course that one can match it to their speakers, a VERY big proviso). I knew to a very high certainty that my speakers would be a great match up with this amp...and at this point, I am right.

I seriously wonder about the heat build up being that valid.

Why? Because running the twenty KT150 Ayon Orthos amps in my system I was seriously surprised on just how cool they ran. And that's 400 Watt/channel in pentode mode. My 211 based amps chuck out WAY, WAY more heat simply running four 211 valves (two per monoblock) and they are nominally rated at 80 Watts.

 

[Zero000]

The filaments hardly looked lit on the Ayons, and you could touch them in use. Try touching one of the 211s and it is serious pain and burn.

 

[DaveyF]

I seriously wonder about the heat build up being that valid.

Why? Because running the twenty KT150 Ayon Orthos amps in my system I was seriously surprised on just how cool they ran. And that's 400 Watt/channel in pentode mode. My 211 based amps chuck out WAY, WAY more heat simply running four 211 valves (two per monoblock) and they are nominally rated at 80 Watts.

All these amps are of a different design. My JA30 Mk2's run pure class A only. That results in the tubes running a little hotter. Keeping in mind that I am in a small room, and the heat factor becomes a consideration. Your Ayon amps probably run cooler compared to what you are used to ( and also since they are only running in pentode mode is a big factor), but I suspect that they would heat up my little room in no time at all. The KT150 is a large tube and as such can give off some decent heat. Put twelve or more of them into a chassis and run it pure class A, I think you have now just created a heat engine.

Bruce, I am hoping ( and pretty sure) that the new Jadis is a lot more reliable than the prior models. Particularly since the old JA30 wasn't that unreliable in the first place.

 

[microstrip]

The JA 200 Mk1 never impressed me. Their limits were always too easily reached and when passed.....one expected failures to quickly follow. (...)

Contrary to many people expectations the JA 200 mk I is a monster of weight, size, heat, number of tubes but not of power. It is an amplifier rated at 160W class A but can not go above 130W, preferably peaking around 100W. It is an amplifier for those who want the class A purity at high class A power, not a class A/B like Audio Research, cj or VTL to name a few with similar number of tubes.

It should be operated with adequate speakers in its power range and then as the Stereophile reviewers long ago said : "With this caveat in mind, the JA 200 still qualifies as one of the most musically appealing amplifiers money can buy." or another reviewer "In the meantime, I'm proud and happy to own the Jadis JA 200s as my reference amps. The joy they give is the knowledge that another musical thrill will always be only a flick of the switch away."

Read more at https://www.stereophile.com/content/jadis-ja-200-monoblock-power-amplifier#u9oeEPWRQsze4XUj.99

I now have three pairs of power amplifiers in my room - and considering my preferences and loudness needs I am sure that a JP200 mkI or mkII would also be an excellent company to the XLF's! But then I would also want a JP80 ...

Considering reliability, we should remember the OTLs - used with good tubes and proper speakers they will give you great music for a lifetime, just changing the tubes. You should also check your mains - both these amplifiers need a stable mains. Use them with wrong speakers and you enter the nightmare of breakdowns and fireworks associated with amplifiers having high energy power supplies.

 

[Zero000]

All these amps are of a different design. My JA30 Mk2's run pure class A only. That results in the tubes running a little hotter. Keeping in mind that I am in a small room, and the heat factor becomes a consideration. Your Ayon amps probably run cooler compared to what you are used to ( and also since they are only running in pentode mode is a big factor), but I suspect that they would heat up my little room in no time at all. The KT150 is a large tube and as such can give off some decent heat. Put twelve or more of them into a chassis and run it pure class A, I think you have now just created a heat engine.

Bruce, I am hoping ( and pretty sure) that the new Jadis is a lot more reliable than the prior models. Particularly since the old JA30 wasn't that unreliable in the first place.

They run in triode mode too. Not observably hotter, and my room isn't huge. The 211 amps are only about 20% efficient, hence the heat.

They were Ked's amps, now long gone. They tried to drive some Divas after I had them, but the owner went for some ARC 250 amps instead.

 

[microstrip]

I seriously wonder about the heat build up being that valid.

Why? Because running the twenty KT150 Ayon Orthos amps in my system I was seriously surprised on just how cool they ran. And that's 400 Watt/channel in pentode mode. My 211 based amps chuck out WAY, WAY more heat simply running four 211 valves (two per monoblock) and they are nominally rated at 80 Watts.

Unless your speakers are very inefficient or you listen very loud, usually the key parameter for heating the room is idle power consumption of the amplifier. Curiously all the monoblocks (SS or tube) I have in my room have around 350-400 watt each and naturally heat the room similarly.

 

[Ron Resnick]

Has anyone compared a JA80 Mk. II (or any Jadis Mk. II amplifier) to the Absolare 85 Push-Pull amplifier?

 

[DaveyF]

Has anyone compared a JA80 Mk. II (or any Jadis Mk. II amplifier) to the Absolare 85 Push-Pull amplifier?

Ron, I highly doubt anyone in the world has had the opportunity to do this 'AB'. The Absolare 845 mono block puts out about 52 watts/ch....in triode mode ( unless you are talking about the 845 push pull model...which is a little higher output, but IME far less pure sounding). The price of the amp is a lot higher than the Jadis JA80 Mk2. IMO, the Absolare 845 Triode competes more with my Jadis JA30 Mk2 due to its power output and at a far higher price! I have heard the Absolare on a couple of occasions...as they say, not my cup of tea; at all! YMMV.